US2461517A

US2461517A - Spray gun for coating the interior of conduits

Info

Publication number: US2461517A
Application number: US571487A
Authority: US
Inventors: John C Carnevale
Original assignee: Individual
Current assignee: Individual
Priority date: 1945-01-05
Filing date: 1945-01-05
Publication date: 1949-02-15
Anticipated expiration: 1966-02-15

Description

Feb. 15, 1949. J, c, CARNEVALE' 2,461,517

SPRAY GUN FOR COATING THE INTERIOR OF CONDUITS Filed Jan. 5, 1945 2 Sheefs-Sheef 1 Feb. 15, 1949. J, a, CARNEVALE 2,461,517

SPRAY 01m FOR comma 'm'E IX'I'ERIOR or coununs Filed Jan. 5. 1945 2 Sheets-Sheet 2 5 52 V 1r re Patented Feb. 15, 1949 SPRAY GUN FOR COATING THE INTERIOR -or CONDUITS John C. Carnevale, Menlo Park, Calif.

Application January 5, 1945, Serial No. 571,487

4 Claims. (CI. 91-44) (Granted under the act of March 3, 1883, as

piping for conveying salt water to the various,

parts of the ship for fire control and other purposes. The piping and conduits which are employed in such systems are internally coated with protective compositions to prevent undue corrosion from the sea water. Heretofore, the coating has been applied by removing the pipes and conduits, section by section, from the ship and submerging each section in a bath of the coating composition, removing it, hanging it up to drain, allowing it to dry, and then reinstalling it in the ship. There are disadvantages incident to such procedure, namely, the necessity, of tying up the ship for a considerable period, of removing all the piping and valves connected thereto which involves considerable labor and time, a waste of amended April 30, 1928; 370 O. G. 75?) 'their opposite ends, means for connecting said the coating composition and damage to the coated surfaceof the conduit during reinstallation.

It is an object of this invention to provide means with which the inside surface of hollow bodies, specifically piping and conduits, may be coated with a protective composition in situ, which will be effective in straight or angular piping, which will be inexpensive and easy to operate.

As illustrated herein, invention resides in means movable lengthwise of a hollow member adapted to emit a diffused cloud of a coating material from substantially a point source, substantially at the longitudinal axis of the hollow member, radially outward, and supporting means for automatically maintaining the aforesaid means concomitant with the longitudinal axis of the hollow member. More specifically, in one form the aforesaid means comprise an articulated body having a nozzle attached to one ,end and a supply conduit attached to the opposite end, the articulated sections of the body having attached thereto, radially disposed adjustable arms adapted to support the articulated body in concentric relation with respect to the hollow body, and anti-friction rollers at the ends of the arms adapted to engage the inside surface of the hollow body, and thereby to facilitate movement of the device longitudinally. In another form of the invention, there is associated with the first menelongated members to said first named means, means adjustable longitudinally of the hollow body to expand the connecting means-radially, and yieldable means opposing the expansion'of said connecting means.

The invention will now be described in detail with reference to the accompanying, drawings,

in which:

Fig. 1 is av plan view of the spray coating device which forms the subject matter of thepresent invention; i I

Fig. 2 is a perspective view of the spray coating device as seen looking at the nozzle end thereof;

Fig.- 3 is a front view looking directly at the nozzle; I

Fig. 4 is a plan view showing the articulated parts thereof at an angle with respect to each other as would be the case when the device was forced around a bend in the conduit being coated;

Fig. 5 is a longitudinal section through a modified form of the spray coating device;

Fig. 6 shows a section on the line 6-6 of Fig. 5 looking from the nozzle rearwardly and illustrating the position of the device inside of a conduit C; and

Fig. '7 is a modified form of the invention shown in Fig. 5 in which each conduit contacting shoe is provided at its opposite ends with antifriction devices.

Referring to the drawing, the spray coating device for coating the inside .of conduits and piping is represented generally by the reference character 10 and consists of a spray nozzle f2, adapted to eject a diffused cloud of coating composition radially outward and which is supported centrally of a conduit C such as that shown in Fig. 3 byradially disposed arms Hi and I6 arranged as will be related hereinafter. The nozzle 12, which is of standard construction and adjustable to give a suitable spray of coating material. is threaded onto one end of a hollow body 18 and to the opposite end of this hollow body is threaded a hollow handle 20 through which air and the coating compositionare introduced to the hollow body I8 and the nozzle |2. The hollow handle 20 has at its free end a threaded portion over whichmay be clamped a flexible supply conduit (not shown) for' conducting the coating composition from high pressure supply receptacles. A pair of

discs

22 and 24 are mounted on the body is, preferably threaded vided with a slot 82. Through these slots are,

passed

screws

84 and 88, respectively, the screws being threaded into the

discs

22 and 24 and serving to hold the arms l4 and i8 rigidly clamped against one face of the disc. By slacking off on the

screws

84 and 88, the arms may be adjusted inwardly r outwardly relative to the discs to provide for adjusting the spray coating device so that it has a freely sliding fit in the conduit to be coated. Each of the arms l4 has at its terminal end a forwardly projecting portion 88- reception of discs 44 which are journaled therein. The discs 48 and 44 at the ends of the respectlve arms are adapted to bear against the inside surface of the conduit to which a coating is to be applied, and to facilitate movement of the spray coating device through the conduit. In

order to reduce the frictional contact between the discs and the wall of the conduit and thereby to increase mobility of the spray coating device as much as possible, the discs 48 and 44 are provided with a sharp peripheral edge which affords substantially line contact between them and the inner surface of the conduit. The adjustment of each arm 14 is limited only by the length of the slot 88. The adjustment of the arms i8 inwardly, however, is limited by the periphery of the disc 24 since the forwardly and rearwardly projecting portion 42 will engage the periphery of the disc 24 when the arms 18 are moved inwardly. To permit the arm l8 to be adjusted inwardly to the same extent as the arms i'4, slots or notches 48 are formed in the disc 24 oi such width as to accommodate the portion 42. It may also be necessary to notch the portion 42 at 48 it the portion 42 is not of uniform thickness throughout. In order that the spray coating device may be useful not only in straight conduits, but also in conduits having bends therein, the body ill of the spray coating device is articulated, the articulation being provided for by a ball 88 and socket 52. This arrangement permits substantially universal movement between the fore part of the coating device which carries the nozzle l2 and'the rear part of the device which includes the handle 28. Slots 84 are formed in the socket 82 to accommodate the character 88, comprises a nozzle 88 threaded on-. to one end of a hollow body 82 to thempposltethe pins 18 and I8 are journaled arms 18, which extend inwardly toward each other and are pivoted on the opposite ends oi pins Ti and 18 fixed transversely in posts 18, the latter being formed integral with shoes 88 having substantially convex surfaces adapteli, as shown in Fig. 6, to bear against the inner surface of a conduit C. The

. changed to accommodate whatever diameter of shoes 88 being equidistant from each other form a three point support for the spray device within the conduit, and hence, hold it centrally thereof. Between the legs 88 and the sleeve 88 there is disposed a washer 82 and a spring 84, the latter bearing at one end against the lugs 88 and at its opposite end against the washer 82, by its force opposing movement of the sleeve 88 toward the lugs 88. The sleeve 88 is provided with an enlarged knurled head 88, by which the sleeve may be rotated to move it longitudinally on the body 82 toward or away from the lugs 88, thereby to expand or contract the shoes 88 with respect to the body 82. It is evident that by this construction the radial position of the shoes may be conduits is tobe coated. While the aforesaid shoes '88 are provided with smooth convex surfaces which permits the device to slide through the conduit C, if the conduit is of considerable length, it is desirable to reduce the friction between the device and the inner surfaces of the conduit and this may be done as illustrated in Fig. 7 by bifurcating the opposite ends of the shoes and journaling discs 88 therein, similar tothe disc 48 described in the form of the invention shown in Fig. l.

Preparatory to using the device shown in either of its forms, the operator adjusts the radial arms i4 and I8 or the sleeve 88 so that the rollers 48 and 44 or the shoes 88 freely fit the inside diameter of the conduit which is to be coated. The supply line is then connected to the handle 28 or to the nipple 84, and the coating material together with air for forcing it through the nozzle is permitted to enter the device. The character of the spray coating material which is to be applied to the inside surface of the conduit, will be determined by adjustment of the spray nozzle i2 in the usual manher, and since such adjustment of a nozzle is common in practice, it will not be described herein. The device is then pushed through the conduit slowly and the coating material will be applied evenly and uniformly over the entire inner surface of the conduit by reason of the fact that the rollers 48 and 44 or the shoes 88 hold the spray nozzle i2 centrally of the conduit. Where the conduit has bends in it, it is necessary to use the form of the invention shown in Fig. 1, and also where the conduit is of great length. In short straight conduits, the form of the invention shown in Fig. 5 may satisfactorily be employed, however, if this is to be used for great lengths of conduit its movement through the end of'whi'eh is threaded a nipple 84 adapted to be connected to a flexible conduit (not shown) for conducting the coating material and air to the nozzle. Formed integral with the body 82 adiacentto the nozzle 88 are three radially disposed lugs 88. At the opposite'end near the nip pie 84 there is a sleeve 88 threaded on the body 82, the sleeve having telescopically disposed thereon, a collar 18. The lugs 88 and the collar 18 are provided with hearing posts I2 and 14 having extending therethrough from opposite sides. pins I2 and 78. on the opposite ends of conduit may greatly be facilitated by use of the discs 88, as shown in Fig. 7. It is evident that by Using the device described in its various forms, the coating may be carried out without removing the piping from the ships. and hence the coating operation may be performed without dismantling' the entire piping system and at a minimum loss in time.

The invention described herein may be manufactured and used by or for the Government of the United States of America for governmental purposes without the payment of any royaltiesv thereon or therefor.

What is claimed is:

l. A device for coating the inside surface of an elongated hollow member, comprising means movable-lengthwise of the hollow member adapted to emit a diflused spray of coating composition from a substantially point source, substan-' 2. A device for coating the inside surface of anelongated hollow member, comprising means movable lengthwise of the hollow member adapted to emit a diffused spray of coating composition from a substantially point source, substantially at the longitudinal axis of the hollow member radially outward, a two part articulated support, one part of which is universally movable with respect to the other, radial arms extending from each part, and anti-friction discs at the ends of said arms.

3. A device for coating the inside surface of an elongated hollow member, comprising means movable lengthwise of the hollow member adapted to emit a diffused spray of coating composition from a substantially point source, substantially at the longitudinal axis of the hollow member, radially outward, a two part articulated support, the parts of which are universally movable relative toeach other. radially disposed arms extending from each part, the radial arms of anon-s17.

one part terminating in single point wall oon-' tacting means and the radial arms of the other part terminating in two point walls contacting 7 means.

4. A device for coating the inside surface of an elongated hollow member, comprising means movable lengthwise of the hollow member adapted to emit a diffused spray of coating composition from a substantially point source, substantially at the longitudinal axis of the hollow member, radially outward, said means comprising a, length of pipe, aspray nozzle fixed to one end thereof,'a

I conduit fixed to the other end thereof, said length of pipe being articulated between its ends to pro:

vide elements universally movable with respect to each other, a circular plate threaded onto each element of the pipe, aplurality of arms, means for adjustably fastening each arm to the circular plate for movement with respect thereto in a direction substantially normal to a radial line ex- The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,942,876 Perkins Jan. 9, 1934 1,951,221 Tate ....'i Mar. 13, 1934 2,017,042 Dougherty Oct. 15, 1935 2,348,714 De Flore May 16, 1944 2,353,951

Wood July 18, 1944